Vienna Physicists Create Tap-Proof Waves

Scientists at the Vienna University of Technology (TU Vienna) have developed a method to steer waves on precisely defined trajectories, without any loss. This way, sound waves could be sent directly to a target, avoiding possible eavesdroppers. Tossing a ball to someone without anyone else being able to catch it is simple. Calling out to someone without anyone else hearing it is much harder. There seems to be a fundamental difference between waves and solid objects: a ball moves along a straight trajectory, whereas waves spread into all directions simultaneously. Quantum physicists at the Vienna University of Technology are proposing a new method to let waves travel on simple, straight trajectories. Applying this idea to acoustic waves, it would be possible to communicate with a person at the other side of a room without anyone else being able to hear anything.